JP2001304464A - Duct for high temperature gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a duct for high temperature gas allowing the heat insulation to have a long lifetime, capable of maintaining the heat-insulating effect for a long period, and accordingly equipped with a high reliability. SOLUTION: The duct for high temperature is composed of an outer cylinder, an inner cylinder positioned inside the outer cylinder, and a heat insulation located between the outer and inner cylinders and fixed to the outer cylinder separately from the inner cylinder, wherein a space is reserved between the inner cylinder and heat insulation so that the vibration of the gas passing through the duct and/or a variation of the internal pressure is received by the inner cylinder, and thereby transmission to the heat insulation is suppressed, while the space admits free expansion and contraction of the inner cylinder in the radial direction, and even in case the inner cylinder makes thermal expansion to cause its diametric enlargement, contacting of the inner cylinder with the heat insulation is avoided, which allows preventing the heat insulation from going in breakage. Also the space prevents the vibration of the inner cylinder from making direct transmission to the heat insulation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duct through which a high-temperature gas flows, for example, used in a gas turbine, a pressurized fluidized-bed boiler, a high-temperature gas-cooled reactor as a kind of nuclear reactor, and the like.

[0002]

2. Description of the Related Art As a hot gas duct, for example, in a gas turbine for power generation, a turbine is rotated by high-temperature combustion gas. The combustion gas is then discharged out of the gas turbine, guided to a steam turbine exhaust gas boiler through an exhaust duct, or exhausted from an exhaust chimney. High-temperature gas passes through the inside of the exhaust duct, and the high-temperature gas duct needs to have a heat insulating structure in order to suppress heat radiation outside the duct.

FIG. 11 is an axial sectional view showing a part of a conventional exhaust duct (high-temperature gas duct) for discharging exhaust gas from a gas turbine. The exhaust duct includes a cylindrical body 101 having pressure resistance performance, a heat insulator 102,
It is composed of a holding plate 103, a bolt 104, a washer 105, a nut 106 and the like.

The heat insulator 102 is made of felt-like ceramic fiber or glass fiber, and is pressed in the outer peripheral direction by a pressing plate 103 to abut on the inner peripheral surface of the cylindrical body 101. Adjacent holding plates 103 have overlapping ends. Bolt 104 is heat insulator 102, holding plate 1
03 and the washer 105. Bolt 10
One end of 4 is fixed to the cylindrical body 101 by welding, and a nut 105 is screwed into the other end.

A bolt 104 provided on a holding plate 103
The inner diameter of the hole 104a is sufficiently larger than the outer diameter of the bolt 104, and is in a so-called play state. Therefore,
The holding plate 103 is slidable in a gap formed by upper and lower nuts 106 and upper and lower washers 105. The slide absorbs thermal expansion and contraction of the holding plate 103. Although the high-temperature gas a passes through the inside of the exhaust duct (below the holding plate 103 in FIG. 11) as shown by the arrow, the exhaust duct is insulated by the heat insulator 102 and the movement of heat to the outside of the exhaust duct is suppressed.

Although the size of the holding plate 102 is not particularly limited, for example, the length is about 1 m, the width is about 1 m, and the thickness is 2 m.
m. The thickness of the cylinder 101 is, for example, 5 m.
m to about 6 mm. The thickness of the heat insulator 102 is, for example, about 200 mm. In addition, bolt 10
4 is, for example, M16 volts, and adjacent bolts 10
The interval between 4,104 is, for example, 300 mm.

[0007]

In the above-described conventional exhaust duct (high-temperature gas duct), exhaust gas (high-temperature gas a) passes at a speed of about 90 m / s, and its internal pressure is equal to the atmospheric pressure +
Although it is about 75 hpa, with the fluctuation of about ± 20 hpa, the heat insulator 102 may be deteriorated due to the passage of the high-temperature gas a and the fluctuation of the internal pressure, and the life thereof may be shortened.

In addition, since mechanical vibration generated in the gas turbine is transmitted to the exhaust duct, the vibration may deteriorate the heat insulator 102 and shorten its life. When the heat insulator 102 is deteriorated, there is a problem that the heat insulating effect is reduced.

Further, since the exhaust gas passing through the exhaust duct has a high temperature of about 650 ° C., the holding plate 103 thermally expands,
Although this thermal expansion is absorbed by the sliding of the holding plate 103 as described above, it is difficult to completely set the positional relationship between the bolts 104 and the holding plate 103 that are provided in large numbers. May be damaged.

When the holding plate 103 is damaged, the heat insulator 10
2 is blown off by the exhaust gas flow,
In addition, there is a problem that not only does the heat insulator 102 fall into the exhaust duct and the heat insulating effect is reduced, but in some cases, the gas turbine must be stopped for a long time to repair the exhaust duct. .

Similar problems have been found not only in exhaust ducts of gas turbine plants, but also in ducts through which high-temperature gas passes, such as pressurized fluidized-bed boilers and high-temperature gas furnaces.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a high-temperature gas duct in which the life of a heat insulator can be extended, the heat insulating effect is maintained for a long time, and the reliability is improved. Is the subject.

[0013]

Means for Solving the Problems (1) The present invention has been made to solve the above problems, and as the first means, an outer cylinder and an inner cylinder are located inside the outer cylinder. An inner cylinder, and a heat insulator positioned between the outer cylinder and the inner cylinder and fixed to the outer cylinder at a distance from the inner cylinder and separated from the inner cylinder, wherein a space is provided between the inner cylinder and the heat insulator. And a duct for high-temperature gas.

According to the first means, since the high-temperature gas duct (hereinafter, also simply referred to as "duct") is provided with the inner cylinder inside the heat insulator, the vibration and the internal pressure fluctuation of the gas passing through the duct are provided. Is received by the inner cylinder, transmission to these insulators is suppressed, and since the space allows free expansion and contraction in the radial direction of the inner cylinder, even if the inner cylinder expands due to thermal expansion. Contact between the inner cylinder and the heat insulator is avoided, and damage to the heat insulator is prevented. Further, the space prevents the vibration of the inner cylinder from being directly transmitted to the heat insulator.

(2) As the second means, the first means
In the high-temperature gas duct of the means, the heat insulator is composed of a bag and a powdered heat insulating material filled in the bag, and the heat insulator is fixed to the outer cylinder by being pressed against the outer cylinder. It is intended to provide a high-temperature gas duct characterized by comprising:

According to the second means, in addition to the function of the first means, the heat insulator is fixed to the outer cylinder by being pressed against the outer cylinder. It is deformable to some extent, and tends to expand in the axial and circumferential directions of the duct by being pressed against the outer cylinder. Thereby, the gap between adjacent heat insulators is filled, and the heat insulating effect is enhanced. Further, since the heat insulator follows the deformation even when the duct is deformed due to thermal expansion, no gap is generated between adjacent heat insulators, and the heat insulating effect is maintained.

(3) As a third means, there is provided a high-temperature gas duct according to the second means, wherein the powdery heat insulating material is a porous inorganic powder. .

According to the third means, in addition to the action of the second means, a preferable powdery heat insulating material is a porous inorganic powder, which improves the heat resistance of the heat insulator.

(4) As a fourth means, there is provided a high-temperature gas duct according to the second means, wherein the bag is formed of silica cloth.

According to the fourth means, in addition to the action of the second means, a preferable material of the bag is silica cloth, which also improves the heat resistance of the heat insulator. Furthermore, since the silica cloth is less likely to conduct heat than a metal material, the amount of heat radiation is reduced as compared with a case where a powdery heat insulating material is filled in a metal container to form a heat insulator. .

(5) As a fifth means, in the high-temperature gas duct according to any one of the first means to the fourth means, the inner cylinder is divided into a plurality of cylindrical portions in the axial direction, Provided is a high-temperature gas duct, characterized in that an expansion joint that can expand and contract in the axial direction is provided between cylindrical portions.

According to the fifth means, in addition to the operation of any of the first to fourth means, the axial thermal expansion of the cylindrical portion of the inner cylinder is achieved by the division of the inner cylinder and the expansion joint. Is absorbed.

(6) As a sixth means, in the high-temperature gas duct according to the fifth means, the expansion joint has a link composed of a pair of nodes connected to each other by a fulcrum shaft at one end. The other end of each node is pivotally supported by the adjacent cylindrical portion, and the fulcrum shaft is connected to the outer cylinder via a support tool joined to the inner peripheral surface of the outer cylinder. A hot gas duct is provided.

According to the sixth means, in addition to the operation of the fifth means, the divided cylinder portions of the inner cylinder are connected to each other so as to be expandable and contractable by a link suitable for strength, reliability and the like. The inner cylinder can be suspended from the outer cylinder via.

(7) As a seventh means, in the high-temperature gas duct of the sixth means, the fulcrum shaft of the link and the support are provided with a joint for absorbing the movement of the inner cylinder in the radial direction. And a duct for high-temperature gas, wherein the duct is connected to the duct through a hot gas.

According to the seventh means, in addition to the function of the sixth means, since the fulcrum of the link and the support are connected via the joint, the joint can be used in the radial direction of the inner cylinder caused by thermal expansion or the like. Movement to is absorbed.

(8) As an eighth means, in the high-temperature gas duct of the sixth means, a protective ring is provided on an outer peripheral surface of the outer cylinder corresponding to a position where the support member of the outer cylinder is joined. A high-temperature gas duct is provided.

According to the eighth means, in addition to the function of the sixth means, a load of the inner cylinder is applied to a portion of the outer cylinder to which the support is joined, but the load corresponding to the position where the support is joined is provided. The protection ring provided on the outer peripheral surface of the outer cylinder improves the strength of this portion, and prevents the outer cylinder from being damaged by the load on the inner cylinder.

(9) As a ninth means, in the high-temperature gas duct of the first means, between the axial end of the outer cylinder and the end of the cylindrical body of another adjacent duct. In addition, the present invention provides a high-temperature gas duct, which is provided with an outer cylinder expansion joint that can expand and contract in the axial direction.

According to the ninth means, in addition to the function of the first means, it is possible to absorb not only the thermal expansion of the inner cylinder but also the outer cylinder in the axial direction, and to connect the duct of another device to the cylindrical body. Can be easily done.

(10) As a tenth means, in the high-temperature gas duct of the ninth means, the outer cylinder expansion joint has one fulcrum pivotally supported by the outer cylinder and the other fulcrum being the other duct. A plurality of composite links in the circumferential direction, which are pivotally supported by the cylindrical body, have an intermediate fulcrum between the two fulcrums, and the one fulcrum, the intermediate fulcrum and the other fulcrum are extended and contracted at equal intervals, And a plurality of annular plates respectively attached to the two fulcrums and the intermediate fulcrum, and a heat insulator composed of a bag and a powder heat insulating material filled in the bag, and attached to the inner peripheral surface of the annular plate, A high-temperature gas duct, comprising: a diaphragm that covers a space between an axial end of the outer cylinder and an end of a cylindrical part of another adjacent duct.

According to the tenth means, in addition to the function of the ninth means, relative movement due to thermal expansion between the outer cylinder and the cylindrical body of the other duct in the outer cylinder expansion joint is absorbed by the composite link, Since the distances between the fulcrums of the links are equal, the amount of relative movement is distributed to a plurality of annular plates, and the heat insulator provided on the inner periphery of the annular plate is swellable by the amount of movement because the heat insulator is freely deformable. Does not occur, there is no lack of heat insulating action, and the diaphragm functions as an outer cylinder to form a continuous hot gas duct.

(11) As an eleventh means, in the hot gas duct of the ninth means or the tenth means,
The tube body of the other duct is an intermediate cylinder provided to be connected to an end of the cylinder body of the outer surface heat retaining duct provided with a heat insulator on the outer peripheral side, and the intermediate cylinder is an outer peripheral surface and an inner peripheral surface. And a high-temperature gas duct characterized by comprising a heat insulator on both sides.

According to the eleventh means, in addition to the function of the ninth means or the tenth means, the hot gas duct for keeping the inside heat is separated from the duct for keeping the outside heat in another device part or another duct. It can be easily connected.
In this case, since the outer heat retaining duct connects the inner and outer surfaces to the outer cylinder expansion joint via the warmed intermediate cylinder, the stress on the outer cylinder expansion joint due to the difference in thermal expansion between the inner heat retaining duct and the outer cylinder is large. To reduce.

(12) As a twelfth means, in the hot gas duct of the ninth means or the tenth means,
The high-temperature gas duct is characterized in that the other duct is a tubular body of an inner surface heat-retaining duct provided with a heat insulator on the inner peripheral side similarly to the outer cylinder.

According to the twelfth means, in addition to the function of the ninth means or the tenth means, the outer cylinder of the hot gas duct for keeping the inner surface warm is connected to the outer cylinder of the adjacent hot gas duct for keeping the inner surface warm. The duct can be easily connected, and becomes a high-temperature gas duct for keeping the inner surface warm, in which not only the inner cylinder but also the outer cylinder are connected in a stretchable manner.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A high-temperature gas duct according to a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is an axial sectional view showing a part of the high-temperature gas duct according to the present embodiment. FIG. 2 is a cross-sectional view (transverse cross-sectional view) taken along line AA in FIG. 1 and showing a part of the high-temperature gas duct along a direction perpendicular to the axial direction. FIG. 1 corresponds to the view taken in the direction of arrows BB in FIG.

The high-temperature gas duct according to the present embodiment includes an outer cylinder 1, a heat insulator 3 and an inner cylinder 5, and the inner cylinder 5 includes an expansion joint 7 described later. The high-temperature gas a moves inside the inner cylinder 5 (below the inner cylinder 5 in FIG. 1) in the direction indicated by the arrow in FIG.

In this embodiment and other embodiments described later, the description of the cross section of the entire high-temperature gas duct is circular as shown in FIG. 2 as an example. Most are described and generally circular, but may be, for example, elliptical or rectangular. Further, the inner size may gradually change along the axial direction.

The outer cylinder 1 is located on the outermost side of the hot gas duct. Since the outer cylinder 1 also functions as a pressure-resistant container, it is made of a material having excellent pressure resistance, such as an SS material. The thickness of the outer cylinder 1 is not particularly limited, and a thickness that can withstand the pressure of the passing high-temperature gas is appropriately set.

The heat insulator 3 is in contact with the inner peripheral surface of the outer cylinder 1. The heat insulator 3 has a substantially block shape, and a large number thereof are arranged in parallel. A metal protection plate 9 is in contact with the inner cylinder 5 side of the heat insulator 3. A wire 11 whose one end is joined to the inner peripheral surface of the outer cylinder 1 is lowered between the adjacent heat insulators 3. A leaf spring 13 is attached to a lower end of the wire 11.

The metal protection plate 9 is pressed radially outward (that is, in the direction of the outer cylinder 1) by the leaf spring 13, and the heat insulator 3 is pressed radially outward by the metal protection plate 9. . Thereby, the heat insulator 3 is fixed to the outer cylinder 1.

Although not shown, a silica cloth may be arranged between the heat insulator 3 and the metal protection plate 9.
This silica cloth contributes to improvement of the heat insulating effect at the joint of the heat insulator 3 and protection of the bag of the heat insulator 3 at the joint of the metal protection plate 9.

Although the dimensions of the heat insulator 3 are not particularly limited,
For example, the width is about 300 mm, the length is about 1000 mm,
The thickness is about 100 mm. The dimensions of the metal protection plate 9 are, for example, about 300 mm in width, about 300 mm in length, and about 0.5 mm in thickness.

A plurality of (three in FIG. 1) metal protection plates 9 are in contact with one heat insulator 3 in the axial direction of the duct. A gap is provided between adjacent metal protection plates 9, 9, and the gap absorbs thermal expansion of the metal protection plate 9.

The heat insulator 3 is suspended by the wire 11 as described above. However, since the wire 11 has a small diameter, a small amount of heat is conducted. Therefore, there is no state in which a large amount of heat is conducted through the bolts 104 as in the conventional exhaust duct shown in FIG. 11, and the amount of heat radiation from the duct is suppressed. In addition, since the mounting is performed by the wire 11, there is no need to consider a countermeasure against loosening unlike the conventional mounting using bolts and nuts, thereby improving work efficiency.

FIG. 3 is an overall side view of the inner cylinder 5. As shown in FIG. 3, the inner cylinder 5 has a frame 15 and a panel 17, and the panel 17 is fixed to the frame 15 by rivets 19. ing. The frame 15 is stretched in the axial direction, the circumferential direction, and the like of the duct. The inner cylinder 5 is divided into a plurality of cylinder portions 21. A flange 23 is formed at an end of each cylindrical portion 21, and the flanges 23 of the adjacent cylindrical portions 21 face each other at a predetermined interval.

As shown in FIG. 3, the inner cylinder 5
In some cases, the cylindrical portion 21 whose axial direction is horizontal and the cylindrical portion 21 whose axial direction is inclined with respect to the horizontal are combined. Also, in FIG.
The arrangement of the frames 5 is schematically shown, but in the actual inner cylinder 5, the interval between the adjacent frames 15, 15 is, for example, 5 mm.
Since it is about 00 mm, more frames 15 are provided than in the state shown in FIG.

As shown in FIGS. 1 to 3, in the high-temperature gas duct of the present embodiment, the inside of the inner cylinder 5 forms a flow path for the high-temperature gas a. Therefore, the impact of the high-temperature gas a and fluctuations in the internal pressure are received by the inner cylinder 5, and transmission to the heat insulator 3 is suppressed. Therefore, deterioration of the heat insulator 3 is prevented. Further, the inner cylinder 5 and the heat insulator 3 are separated from each other, and a space 10 exists between the inner cylinder 5 and the heat insulator 3. The space 10 prevents contact between the inner cylinder 5 and the heat insulator 3 when the inner cylinder 5 expands in diameter due to thermal expansion, and prevents damage to the heat insulator 3. further,
The space 10 prevents the vibration of the inner cylinder 5 from being directly transmitted to the heat insulator 3.

FIG. 4 is a partially cutaway perspective view showing the heat insulator 3 of the high-temperature gas duct of FIGS. The heat insulator 3 includes a substantially block-shaped bag 25 and a powdered heat insulating material 27 filled in the bag 25. With such a configuration, the heat insulator 3 can be deformed to some extent by the load.

When the heat insulator 3 is pressed against the outer cylinder 1 by the leaf spring 13 and the metal protection plate 9 as shown in FIGS. Thereby, the gap between the adjacent heat insulators 3 is filled, and the heat insulating effect is enhanced.
Further, since the heat insulator 3 is freely deformable, even when the duct is deformed due to thermal expansion, it follows this deformation.

Therefore, according to the heat insulator 3 of the present embodiment, no gap is formed between the adjacent heat insulators 3 and a structure in which the heat insulating effect is maintained can be easily obtained.

Further, the powder heat insulating material 27 is preferably a porous inorganic powder, whereby the heat resistance of the heat insulator 3 is improved.

The bag 25 is formed of a cloth including a woven cloth and a non-woven cloth. Suitable cloths include, for example, glass cloth, and among them, silica cloth made of quartz glass is preferable because of its excellent heat resistance. From the viewpoint of preventing the powder heat insulating material 27 from leaking, it is preferable that a plurality of cloths be stacked to form a bag 25 having, for example, a double structure.

In the present embodiment, the heat insulator 3 is constituted by the bag 25 and the powder heat insulator 27. However, the heat insulator 3 is not limited to this, and the powder heat insulator is formed into a panel and solidified. Outer cylinder 1 so that no gap is formed between heat insulators 3
The same can be used as long as it can be attached to the inner peripheral surface of. However, as described above, according to the present embodiment, the heat insulating effect is more preferably and easily achieved.

FIG. 5 is an enlarged sectional view showing the vicinity of the expansion joint 7 corresponding to the portion C in FIG. In FIG. 5, the left cylinder 21a and the right cylinder 21b are shown as the inner cylinder 5. A flange 23a is formed at the right end of the left cylindrical portion 21a. Similarly, a flange 23b is formed at the left end of the right cylindrical portion 21b. Panel 17 of left cylindrical portion 21a
The right end of “a” is separated from the left end of the panel 17b of the right cylindrical portion 21b.

A pair of upper and lower slide plates 2 is provided on the panel 17a of the left cylindrical portion 21a and the panel 17b of the right cylindrical portion 21b.
A slide panel 33 composed of a spacer 9 and a spacer plate 31 is bridged. The inner cylinder 5
And the airtightness of the hot gas a from between the left panel 17a and the right panel 17b is suppressed.

The left flange 23a and the right flange 2
A link 35 to be described later is provided between the link 3b.
The link 35 and the slide panel 33 constitute the expansion joint 7, and the expansion joint 7 absorbs the thermal expansion of the inner cylinder 5 in the axial direction.

FIG. 6 is a view showing a link 3 taken along the line DD in FIG.
It is a top view which shows the vicinity of 5. As shown in FIGS. 5 and 6, the link 35 includes two left nodes 37a and two right nodes 37b. That is, the link 35 is
It has two pairs of nodes 37. One end of each node 37 is supported by a fulcrum shaft 39. Section 37 on the left
The other end of a is pivotally supported by the left L-shaped member 41a, and the L-shaped member 41a is joined to the left flange 23a. Similarly, the other end of the right joint 37b is connected to the right L
The L-shaped member 41b is joined to the right flange 23b.

As described above, since the left cylindrical portion 21a and the right cylindrical portion 21b are connected via the link 35, the joints 37 on both sides of the fulcrum shaft 39 when the inner cylinder 5 expands and contracts. Angle changes. The link 35 is one of the constituent members of the expansion joint 7 and has excellent strength, reliability, and the like. From the viewpoint of improving strength, it is preferable to provide two or more pairs of nodes.

As shown in FIG. 5, a support 43 is provided on a portion of the inner peripheral surface of the outer cylinder 1 corresponding to the outside of the expansion joint 7.
Are joined. The support tool 43 is made of, for example, steel or the like. Although not shown in FIG. 5, as shown in FIG. 2, one end of a leaf spring 45 as a joint is joined to the support 43. The other end of the leaf spring 45 is joined to the fulcrum shaft 39 of the link 35.

That is, the inner cylinder 5 is fixed to the inner peripheral surface of the outer cylinder 1 via the link 35, the leaf spring 45 and the support 43, and the leaf spring 45 expands and contracts the inner cylinder 5 in the radial direction. (That is, diameter expansion and diameter reduction) are absorbed. Such fixing is performed at a plurality of locations at predetermined intervals along the circumferential direction of the duct. Thus, the position of the inner cylinder 5 in the outer cylinder 1 is stabilized.

The support 43 has a curved and meandering cross section as shown in FIG. Accordingly, the substantial overall length of the support 43 is increased, and heat radiation outside the duct via the support 43 is suppressed. Further, the support member 43 is provided with a felt-like ceramic heat insulating material 47 filled in a bag body 46 made of glass cloth or silica cloth, whereby heat radiation to the outside of the duct is suppressed.

A high-temperature gas duct according to a second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a cross-sectional view of a part of the high-temperature gas duct according to the present embodiment, taken along a direction perpendicular to the axial direction.

The configuration of the outer cylinder 1, the inner cylinder 5, the heat insulator 3 and the like of the high-temperature gas duct of the present embodiment is the same as that of the high-temperature gas duct of the first embodiment shown in FIGS. 7, the same parts are denoted by the same reference numerals in FIG. 7 and the description thereof will be omitted. Hereinafter, different points in the present embodiment will be mainly described. This is the same in other embodiments described later.

In the high-temperature gas duct of the first embodiment described above, the leaf spring 45 is used as a joint between the link 35 and the support 43, but the high-temperature gas duct of the present embodiment shown in FIG. In the gas duct, a so-called hanging joint 49 is used instead of the leaf spring 45.

The suspension joint 49 includes two U-shaped members 51, one of which is joined to the support 43, and the other of which is joined to the link 35. I have. Inside each U-shaped member 51, a cylindrical horizontal bar 53 is passed, and the two horizontal bars 53 are connected by a connecting bar 55.

Since the inner dimension of the U-shaped member 51 is sufficiently larger than the outer diameter of the horizontal bar 53, the horizontal bar 53 is
It is rotatable to some extent and movable to some extent. By this rotation and movement, the expansion and contraction of the inner cylinder 5 in the radial direction is absorbed.

Although not shown in FIG. 7, the link 35 is connected to the inner cylinder 5 similarly to the high-temperature gas duct of the first embodiment shown in FIGS.

A high-temperature gas duct according to a third embodiment of the present invention will be described with reference to FIG. FIG. 8 is an axial sectional view showing a part of the high-temperature gas duct according to the present embodiment.

The configuration of the outer cylinder 1, the inner cylinder 5, the heat insulator 3 and the like of the high-temperature gas duct of the present embodiment is the same as that of the high-temperature gas duct of the first embodiment shown in FIGS. Is the same as

In this embodiment, as shown in FIG. 8, a protective ring 57 is provided in a rib shape on the outer peripheral surface of the outer cylinder 1 of the high-temperature gas duct. The protection ring 57 is fixed to the outer cylinder 1 by means such as welding. Protective ring 5
7 is provided corresponding to the position where the support tool 43 is joined to the back side. In this part of the outer cylinder 1, a support 4
Although the load of the inner cylinder 5 is applied via the inner ring 3, the strength of the outer cylinder 1 is improved by the protection ring 57, so that damage of the outer cylinder 1 is prevented.

A high-temperature gas duct according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a cross-sectional view along the axial direction showing a portion where the outer cylinder expansion joint of the duct for high-temperature gas according to the present embodiment is provided.

In this embodiment, a duct (hereinafter, referred to as an “outside heat retaining duct”) 61 provided with the heat insulating body 3 on the outer peripheral surface of the cylindrical body 61 a, and an inner peripheral surface of the outer cylinder 1 are provided. An outer cylinder expansion joint 60 is used at a connection portion with a duct 62 (hereinafter, referred to as an “inner heat-retaining duct”) that is provided with the heat insulator 3 and is kept warm on the inner surface.

The outer cylinder 1, the inner cylinder 5, and the
The configuration of the heat insulator 3 and the like is basically the same as that of the high-temperature gas duct according to the first embodiment shown in FIGS. 1 to 6, but in FIG. It has a structure to attach an outer cylinder expansion joint 60 for connection with the outer cylinder.

At the right end of the outer heat retaining duct 61, a cylindrical body 6 is provided.
1c, an intermediate cylinder 63 is provided.
3 is enlarged to have the same diameter and shape as the outer cylinder 1 of the duct 62 for keeping the inner surface warm, and includes heat insulators 3 on both the outer peripheral surface and the inner peripheral surface thereof;
Its inner and outer surfaces are kept warm.

In the state where the high-temperature gas a is passing through, the temperature near the left end of the intermediate cylinder 63 is high, but the temperature decreases as it approaches the right end due to the effect of keeping the inner surface warm.
The temperature is almost normal near the right end of. Accordingly, the thermal expansion difference between the inner cylinder 2 and the outer cylinder 1 of the duct 62 for keeping the inner surface warm is small, and the stress on the outer cylinder expansion joint 60 due to the thermal expansion difference is drastically reduced.

The outer cylinder expansion joint 60 is provided with a flange 61a provided at the right end of the outer heat retaining duct 61 (ie, the right end of the intermediate cylinder 63) and the left end of the inner heat retaining duct 62 (ie, the left end of the outer cylinder 1 in FIG. 9). ) Flange 6
2a, a plurality of composite links 70 are provided.

FIG. 10 is a plan view of the composite link 70 taken along the line EE in FIG. As shown in FIG. 10, one fulcrum 71 of the composite link 70 is pivotally supported by a bracket 61b attached to a flange 61a of an outer heat-retaining duct 61, and the other fulcrum 72 is attached to a flange 62a of an inner heat-retaining duct 62. An intermediate fulcrum 73 is supported between one fulcrum 71 and the other fulcrum 72 by the bracket 62b.

In the composite link 70, one fulcrum 7
1, the intermediate fulcrum 73, and the other fulcrum 72 are extended and contracted while having a uniform interval by the link configuration.

Further, both fulcrums 71, 72 of the composite link 70
To each of the intermediate fulcrums 73, an annular metal annular plate 74 concentric with the outer cylinder 1 is fixed. On the inner peripheral surface of each annular plate 75, there is provided a heat insulator 3 'in which a bag is filled with a powdery heat insulator, similar to the heat insulator 3 shown in FIG.

The heat insulator 3 ′ is arranged in an arc along the inner peripheral surface of the annular plate 74. That is, the heat insulator 3 ′ has a shape that is long in the circumferential direction of the outer cylinder expansion joint 60, and the arc-shaped heat insulator 3 ′ is continuous to form a ring-shaped heat insulating structure as a whole.

A metal protection plate 9 'is in contact with the inside of the heat insulator 3'. The metal protection plate 9 'is pressed outward by means such as a leaf spring (not shown). Therefore, the heat insulator 3 ′ is also pressed outward by the metal protection plate 9 ′ and is fixed to the annular plate 74. By pressing, the heat insulator 3 ′ is flattened, whereby the gap between the heat insulators 3 ′ and 3 ′ adjacent in the circumferential direction as well as in the axial direction is filled and a heat insulating structure that is continuous in the axial direction is obtained, and the heat insulating effect is enhanced. Can be

The inner cylinder 5 of the duct 62 for keeping the inner surface warm is
The tube of the outer surface heat retaining duct 61 is extended through the connecting portion 76 such as a combination of a slide panel and the like, which extends to the outer tube expansion joint 60 and the inner circumferential side of the intermediate tube 63 and has a proper sealing and expansion function. It is connected to the body 61a.

The outer circumference of the inner cylinder 5 is separated from the heat insulator 3 ′ of the outer cylinder expansion joint 60 and the heat insulator 3 on the inner circumference of the intermediate cylinder 63, and a space 10 is formed.

The relative movement between the outer heat retaining duct 61 and the inner heat retaining duct 62 due to thermal expansion is absorbed by the composite link 70. Since the distances between the fulcrums of the composite link 70 are equal, the amount of relative movement is distributed to the respective insulators 3 ′ provided inside the composite link 70, and the amount of movement between the individual insulators 3 ′ is Become smaller. Since the heat insulator 3 'is deformable as described above, it expands by the movement due to the relative movement, so that there is no gap between the adjacent heat insulators 3' and 3 ', and there is no loss of the heat insulation effect.

In the outer cylinder expansion joint 60, a diaphragm 77 is provided so as to cover the outer peripheral side, and the diaphragm 77 functions as an outer cylinder, so that a continuous high-temperature gas duct can be formed.

The gas impact and fluctuations in the internal pressure are received by the inner cylinder 5 and the space 10 is interposed therebetween, so that transmission to these heat insulators 3 ′ is suppressed.
Expansion and contraction in the radial direction due to pressure, thermal expansion, etc.
Deterioration and breakage of the heat insulator 3 'are prevented.

The outer surface heat retaining duct 61 may be used for another device portion connected to the high-temperature gas duct or another duct portion. However, as described above, the outer cylinder expansion joint 60 is provided. This makes it possible to easily connect the high-temperature gas duct 62 for keeping the inner surface warm and the duct 61 for keeping the outer surface warm. The outer surface heat retaining duct 61 is connected to an outer tube expansion joint 60 via an intermediate tube 63 provided at the end thereof, and the intermediate tube 63 is provided on both the inner peripheral surface and the outer peripheral surface thereof with the heat insulator 3.
Since the inner and outer surfaces are kept warm, the difference in thermal expansion between the outer tube 1 and the duct 62 for keeping the inner surface warm is small, and the stress on the outer tube expansion joint 60 due to the difference in thermal expansion can be drastically reduced.

Although FIG. 9 shows an outer cylinder expansion joint 60 used as a connecting portion between an outer surface heat retaining duct 61 and an inner surface heat retaining duct 62, the outer cylinder expansion joint 60 has the same structure. 60 can also be used as a connecting portion between ducts 62 for keeping the inner surface warm.

That is, in FIG. 9, a left and right inverted inner heat retaining duct 62 is placed instead of the left outer heat retaining duct 61, and a structure in which the left inner heat retaining duct 62 is opposed to the right inner heat retaining duct 62 and connected to each other is possible. is there. This makes it possible to easily connect not only the inner cylinder 5 but also the outer cylinder 1 of the inner heat-retaining duct 62 to the outer cylinder of the adjacent inner heat-retaining duct. A duct for high-temperature gas having an inner surface warmed and connected in a stretchable manner is also obtained.

Although the embodiment of the present invention has been described above, it is needless to say that the present invention is not limited to the above-described embodiment, and various modifications may be made to the specific structure within the scope of the present invention.

[0094]

(1) As described above, according to the first aspect of the present invention, the high-temperature gas duct includes the outer cylinder, the inner cylinder located inside the outer cylinder, the outer cylinder, and the inner cylinder. And a heat insulator which is fixed to the outer cylinder and is spaced from the inner cylinder, and is configured so that a space is provided between the inner cylinder and the heat insulator. Since the inner cylinder is provided inside the heat insulator, vibration and internal pressure fluctuation of gas passing through the duct are received by the inner cylinder, and transmission to these heat insulators is suppressed. In addition, since the space allows free expansion and contraction of the inner cylinder in the radial direction, even if the inner cylinder expands due to thermal expansion, contact between the inner cylinder and the heat insulator is avoided, and damage to the heat insulator is prevented. Is done. Further, the space prevents the vibration of the inner cylinder from being directly transmitted to the heat insulator.

(2) According to the second aspect of the present invention,
2. The high-temperature gas duct according to claim 1, wherein the heat insulator is composed of a bag body and a powdered heat insulating material filled in the bag body, and the heat insulator is pressed against the outer cylinder to form the outer cylinder. 3. Claim 1 because it is configured to be fixed to
In addition to the effect of the invention, the heat insulator is fixed to the outer cylinder by being pressed against the outer cylinder.However, since the heat insulator is a powder inside, it can be deformed to some extent, and is pressed against the outer cylinder. Attempts to extend in the axial and circumferential direction of the duct. Thereby, the gap between adjacent heat insulators is filled, and the heat insulating effect is enhanced. Further, even if the duct is deformed due to thermal expansion, the heat insulator follows this deformation, so that no gap is generated between the heat insulator and the adjacent heat insulator, and the heat insulating effect is maintained.

(3) According to the third aspect of the present invention, in the high-temperature gas duct according to the second aspect, the powder heat insulating material is configured to be a porous inorganic powder. In addition to the effects of the invention described above, a preferred powdery heat insulating material is a porous inorganic powder, which improves the heat resistance of the heat insulator.

(4) According to the fourth aspect of the present invention, in the high-temperature gas duct according to the second aspect, the bag is formed from silica cloth. In addition to the effect, a preferable material of the bag body is silica cloth, which also improves the heat resistance of the heat insulator. Furthermore, since the silica cloth is less likely to conduct heat than a metal material, the amount of heat radiation is reduced as compared with a case where a powdery heat insulating material is filled in a metal container to form a heat insulator.

(5) According to the fifth aspect of the present invention, in the high-temperature gas duct according to any one of the first to fourth aspects, the inner cylinder is divided into a plurality of cylindrical portions in the axial direction, Since the expansion joint is provided between the adjacent cylindrical portions so as to be expandable and contractible in the axial direction, in addition to the effects of the invention of any one of claims 1 to 4, in addition to the division of the inner cylinder, The expansion joint absorbs thermal expansion in the axial direction of the cylindrical portion of the inner cylinder.

(6) According to the sixth aspect of the present invention, in the high-temperature gas duct according to the fifth aspect, the expansion joint includes a link composed of a pair of nodes whose one ends are connected to each other by a fulcrum shaft, The other end of each node of the link is pivotally supported by the adjacent cylindrical portion, and the fulcrum shaft is connected to the outer cylinder via a support joined to the inner peripheral surface of the outer cylinder. Since it is configured to be connected, in addition to the effect of the invention of claim 5, the divided cylinder portions of the inner cylinder are connected to each other so as to be able to expand and contract with each other by a link suitable for strength, reliability, etc. The inner cylinder can be hung from the outer cylinder via.

(7) According to the seventh aspect of the present invention, in the high-temperature gas duct according to the sixth aspect, the fulcrum shaft of the link and the support member absorb the radial movement of the inner cylinder. In addition to the effect of the invention of claim 6, since the fulcrum of the link and the support are connected via the joint, the joint is caused by thermal expansion or the like. The radial movement of the inner cylinder is absorbed.

(8) According to the eighth aspect of the present invention, in the high-temperature gas duct according to the sixth aspect, the outer peripheral surface of the outer cylinder corresponding to the position where the support of the outer cylinder is joined is protected. Since the ring is provided, the load of the inner cylinder is applied to the portion of the outer cylinder where the support is joined, in addition to the effect of the invention of claim 6, but the position where the support is joined is provided. The strength of this portion is improved by the protection ring provided on the outer peripheral surface of the outer cylinder corresponding to the above, and the damage of the outer cylinder due to the load on the inner cylinder is prevented.

(9) According to the ninth aspect of the present invention, in the high-temperature gas duct according to the first aspect, the end of the outer cylinder in the axial direction and the end of the cylindrical body of another adjacent duct may be provided. In this configuration, an outer cylinder expansion joint that can expand and contract in the axial direction is provided between the outer cylinder and the outer cylinder. In addition to the effects of the invention of claim 1, the thermal expansion in the axial direction of not only the inner cylinder but also the outer cylinder is absorbed. To do,
Connection with the duct body of another device can be easily performed.

(10) According to the tenth aspect, in the high-temperature gas duct according to the ninth aspect, the outer cylinder expansion joint has one fulcrum pivotally supported by the outer cylinder and the other fulcrum being the same. A composite link that is pivotally supported by the cylinder of another duct and has an intermediate fulcrum between the two fulcrums, and the one fulcrum, the intermediate fulcrum, and the other fulcrum extend and contract at equal intervals in the circumferential direction. A plurality of annular plates, and an annular plate attached to each of the two fulcrums and the intermediate fulcrum; and a bag and a heat insulating material attached to the inner peripheral surface of the annular plate, which is made of a powdered heat insulating material filled in the bag. And a diaphragm that covers between the axial end of the outer cylinder and the end of the cylindrical part of another adjacent duct, in addition to the effect of the ninth aspect of the invention,
Relative movement due to thermal expansion between the outer cylinder and the cylinder of the other duct in the outer cylinder expansion joint is absorbed by the composite link, and the distance between each fulcrum of the composite link is equal. The heat insulator distributed on the annular plate and provided on the inner periphery of the annular plate is deformable and swells by the amount of movement, so that there is no gap between the heat insulators, there is no loss of heat insulation, and the diaphragm functions as an outer cylinder. , A continuous hot gas duct can be formed.

(11) According to the eleventh aspect of the present invention, in the high-temperature gas duct according to the ninth or tenth aspect, the cylindrical body of the other duct is provided with an outer heat insulating body provided with a heat insulator on the outer peripheral side. An intermediate cylinder connected to an end of a cylindrical body of the duct, wherein the intermediate cylinder has a heat insulator on both the outer peripheral surface and the inner peripheral surface. In addition to the effects of the tenth aspect of the present invention, it is possible to easily connect the high-temperature gas duct for maintaining the inner surface to another device portion or the duct for maintaining the outer surface in another duct or the like. In this case, the outer heat retaining duct connects the inner and outer surfaces to the outer cylinder expansion joint through the heat-retained intermediate cylinder, so the stress on the outer cylinder expansion joint due to the difference in thermal expansion between the inner heat retaining duct and the outer cylinder is greatly increased. Can be reduced.

(12) According to the twelfth aspect of the present invention, in the high-temperature gas duct according to the ninth or tenth aspect, the cylindrical body of the other duct is insulated on the inner peripheral side like the outer cylinder. Since it is configured to be an outer cylinder of an inner heat-retaining duct provided with a body, in addition to the effects of the invention of claim 9 or claim 10, the outer cylinder of the inner heat-retaining high-temperature gas duct is connected to an adjacent inner heat-retaining duct. The high-temperature gas duct can be easily connected to the outer cylinder of the high-temperature gas duct, so that not only the inner cylinder but also the outer cylinder can be extended and contracted to obtain a high-temperature gas duct having an inner surface that is kept warm.

[Brief description of the drawings]

FIG. 1 is an axial sectional view showing a part of a high-temperature gas duct according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is an overall side view of the inner cylinder in the first embodiment.

FIG. 4 is a perspective view in which a part of the heat insulator according to the first embodiment is cut away.

FIG. 5 is an enlarged sectional view of a portion C in FIG.

FIG. 6 is a plan view of the vicinity of the link as viewed in the direction of arrows DD in FIG. 5;

FIG. 7 is a sectional view taken along a direction perpendicular to an axial direction, showing a part of a high-temperature gas duct according to a second embodiment of the present invention.

FIG. 8 is a sectional view taken along an axial direction showing a part of a high-temperature gas duct according to a third embodiment of the present invention.

FIG. 9 is a cross-sectional view along the axial direction showing a portion of a high-temperature gas duct according to a fourth embodiment of the present invention where an outer cylinder expansion joint is provided.

FIG. 10 is a plan view of the composite link as viewed in the direction of arrows EE in FIG. 9;

FIG. 11 is a sectional view taken along an axial direction showing a part of a conventional exhaust duct.

[Explanation of symbols]

 Reference Signs List 1 outer cylinder 3, 3 'heat insulator 5 inner cylinder 7 expansion joint 9, 9' metal protection plate 11 wire 13 leaf spring 15 frame 17, 17a, 17b panel 19 rivet 21, 21a, 21b cylinder portion 23, 23a, 23b flange Reference Signs List 25 bag 27 powder heat insulating material 29 slide plate 31 spacer plate 33 slide panel 35 link 37, 37a, 37b node 39 fulcrum shaft 41a, 41b L-shaped member 43 support member 45 leaf spring 46 bag body 47 ceramic heat insulating material 49 hanging Joint 51 U-shaped member 53 Side bar 55 Connection bar 57 Protective ring 60 Outer tube expansion joint 61 Duct for heat retention on outer surface 61a Flange 61b Bracket 61c Tubular body 62 Duct for heat retention on inner surface 62a Flange 62b Bracket 63 Intermediate tube 70 Composite link 71, 72 Supporting point 73 Intermediate supporting point 74 Annular plate 7 The diaphragm 76 connecting portion

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16L 27/12 F16L 59/10 59/04 59/14 59/10 3/20 E 59/14 F term ( 3H023 AA05 AB07 AC45 AC64 3H036 AA01 AB23 AC01 AE04 AE07 AE13 3H104 JA08 JB02 JC04 JC08 JD02 LB28 LD03 LF11 LG03 MA06 MA08 3H111 AA01 BA03 BA18 BA37 CB21 CB27 DA15 DA26 DB11 DB19 DB22

Claims (12)

[Claims] An outer cylinder, an inner cylinder positioned inside the outer cylinder, and a heat insulator positioned between the outer cylinder and the inner cylinder, spaced apart from the inner cylinder, and fixed to the outer cylinder. A high-temperature gas duct, wherein a space is provided between the inner cylinder and the heat insulator. 2. The high-temperature gas duct according to claim 1, wherein the heat insulator comprises a bag and a powder heat insulator filled in the bag, and the heat insulator is pressed against the outer cylinder. A high-temperature gas duct characterized by being fixed to the outer cylinder by the above method. 3. The high-temperature gas duct according to claim 2, wherein the powdery heat insulating material is a porous inorganic powder. 4. The hot gas duct according to claim 2, wherein the bag is formed of silica cloth. 5. The high-temperature gas duct according to claim 1, wherein the inner cylinder is divided into a plurality of cylinders in an axial direction, and the inner cylinder is axially divided between adjacent cylinders. A high-temperature gas duct comprising an expandable expansion joint. 6. The high-temperature gas duct according to claim 5, wherein the expansion joint has a link composed of a pair of nodes whose one ends are connected to each other by a fulcrum shaft, and the other end of each of the links has the other end. Wherein the fulcrum shaft is connected to the outer cylinder via a support joined to the inner peripheral surface of the outer cylinder. Gas duct. 7. The high-temperature gas duct according to claim 6, wherein the fulcrum shaft of the link and the support are connected via a joint that absorbs movement of the inner cylinder in a radial direction. A duct for high-temperature gas. 8. The high-temperature gas duct according to claim 6, wherein a protective ring is provided on an outer peripheral surface of the outer cylinder corresponding to a position where the support is joined to the outer cylinder. Hot gas duct 9. The high-temperature gas duct according to claim 1, wherein the duct is axially extendable and contractible between an axial end of the outer cylinder and an end of a cylindrical body of another adjacent duct. A high-temperature gas duct comprising an outer cylinder expansion joint. 10. The high-temperature gas duct according to claim 9, wherein the outer cylinder expansion joint has one fulcrum supported by the outer cylinder and the other fulcrum supported by the cylinder of the other duct. A plurality of composite links having an intermediate fulcrum between the two fulcrums, the one fulcrum, the intermediate fulcrum, and the other fulcrum being extended and contracted at equal intervals in the circumferential direction; A plurality of annular plates respectively attached to the, a thermal insulator attached to the inner peripheral surface of the annular plate comprising a bag and a powdered heat insulating material filled in the bag, and an axial direction of the outer cylinder A high-temperature gas duct, comprising: a diaphragm that covers a space between an end and an end of a tubular portion of another adjacent duct. 11. The high-temperature gas duct according to claim 9, wherein a cylinder of the other duct is connected to an end of a cylinder of an external heat-retaining duct provided with a heat insulator on an outer peripheral side. A high-temperature gas duct, characterized in that the intermediate cylinder is provided with a heat insulator on both the outer peripheral surface and the inner peripheral surface. 12. The high-temperature gas duct according to claim 9, wherein the other duct has a tubular body outside an inner heat-retaining duct having a heat insulator on the inner peripheral side similarly to the outer cylinder. High temperature gas duct characterized by being a tube.